麻醉药品（英语：narcotic），又称麻醉品、麻药，最早泛指能够导致人类进入睡眠、昏迷或无知觉状态的药品。在美国，它被用来指称鸦片类药物，如鸦片、海洛英、吗啡、杜冷丁，或是鸦片类药物的衍生物，如可待因酮（oxycodone）、氢可酮（hydrocodone）。因此，这个名词在现代具有负面意思，通常被用来指法律上禁止使用的药品，也就是毒品。

麻醉药品和精神药品是构成毒品的两大来源，联合国制定有《麻醉品单一公约》以控制吸毒问题。

The term narcotic (/nɑːrˈkɒtᵻk/, from ancient Greek ναρκῶ narkō, "to make numb") originally referred medically to any psychoactive compound with sleep-inducing properties. In the United States, it has since become associated with opiates and opioids, commonly morphine and heroin, as well as derivatives of many of the compounds found within raw opium latex. The primary three are morphine, codeine, and thebaine (while thebaine itself is only very mildly psychoactive, it is a crucial precursor in the vast majority of semi-synthetic opioids, such as hydrocodone). Legally speaking, the term "narcotic" is imprecisely defined and typically has negative connotations. When used in a legal context in the U.S., a narcotic drug is simply one that is totally prohibited, or one that is used in violation of governmental regulation, such as heroin or cannabis.